Thirst for Revenge
by YuGiOh-Lover25
Summary: Sebastian is summoned to a girl in this era, who's thirst for revenge has led her a fairly solitary life. Though he claims to not care for the girl, he finds himself risking more than his life to save her from her deranged brother who seems intent on killing off the family line. SebastianxOC, Angst, Fluff, Death and many other references.
1. Prologue

Prologue

* * *

"Well… how did we get in this situation again?" I asked, my eye twitching slightly in annoyance. This was driving me insane, no, beyond insane, and I was very, very close to snapping. Screams and cries came from around me, making it even harder to think straight. As I looked around, watching the idiots around me run around like crazy fools, I felt like yelling my lungs out. The man standing next to me looked equally as frustrated. His eye brow twitched uncontrollably, his shoulders trembling a little.

"I'm not really quite sure, young mistress…" he replied, looking like a cross between shock and anger. One of the women letting out panicked screams came to me, clinging to my arm tightly.

"Oh, Bella! You gotta help us out! The turkey exploded in the oven! What on earth are we going to do!?" cried out the woman, irritating me even more. I turned, letting out some of that anger.

"Just what do you expect a nineteen year old girl to do when her forty five year old sister can't do anything!?" I snapped, my shoulders shaking.

"Come on Bella, you gotta help your big sisters out, please? I'm begging you Isabella" the woman pleaded, two more women peering out the kitchen with pleading expressions. I shook a little more in anger, and then sighed.

"Fine… Sebastian, see what you can do… I'll try and clean this mess up… Make sure they don't make any more explosions" I commanded, making Sebastian put an arm over his chest, directly over his heart as he bowed a little.

"As you wish young mistress" he stated, taking the three sisters away from the room to figure out a new menu. I turned to look at the mess of the kitchen, and then sighed.

"Honestly… How are they the older sisters? Anyone would think I was the older one…" I muttered to myself, pulling my sleeves up to get to work. As I scrubbed at the burnt oven, trying to get off the charcoaled turkey that had stuck to the oven like glue, I thought back to how I'd first met Sebastian. Sebastian wasn't your average man, and he wasn't my boyfriend or anything like that. I knew the true reality of him, he was a demon. With his previous masters he'd been a butler as well as a body guard. With me though, he seemed more like an overprotective big brother. Probably to replace the one I'd lost.

* * *

He hadn't died or anything, but he'd become someone entirely different, stabbing the family in the back quite savagely. I'd definitely lost the man I'd called 'brother' that day. Now just thinking of what that man had become made my blood boil quite furiously. That was how I'd met Sebastian actually. I had been twelve at the time of my first meeting with Sebastian. I'd been at my second eldest sister's house to celebrate Christmas with the family when my brother had finally arrived.

I remembered I'd been so happy to see him, to see my brother Chase. He'd greeted me just as usual, lifting me up and spinning me in the air. I'd laughed so happily, feeling overjoyed. He'd placed me back on the ground and gone in to greet his sisters. Sure, there was a twenty one year difference between me and my brother Chase, he was old enough to be my father, but that was only because of our father remarrying. That's when I had arrived into the picture. When Chase was only four years old, their mother had attacked our father with a knife, going crazy, then ran off with another woman, leaving him to raise four children all on his own.

Fifteen years later, our father Duncan had met my mother Lillia and then two years they'd had me. My mother, Lillia, had been incredibly supportive and nurturing for Chase, and his three sisters, Serina, Taina and Eleanora. Serina was the eldest, the second eldest was Taina and the third eldest was Eleanora. Then the baby of the family was Chase, then myself.

As Chase had greeted the rest of the family, things had gone on as they normally would. We'd opened presents, eaten good food together as a family, laughed and talked about the good times. I had gone outside to play with my nieces that two of my sisters had given birth to that were close to my age, when I'd suddenly smelt smoke. I'd turned running back inside after telling my nieces to remain outside. The house had been set in flames, crimson flames that burnt everything in sight. I'd remained frozen in fear, seeing the bodies of two very precious people lying on the floor, and one very familiar figure stood there, his back turned to me.

I'd called out to him, seeing him turn to look at me, a crazy look in his eyes. I questioned why he'd done such a thing, and he'd replied to me.

"I'm merely setting things in motion. I've seen it, the darkness in this family. It's there, always there, and will remain there unless we all perish!" he'd replied, and then he'd turned his back on me and simply walked away. During my time stuck inside the house, I'd breathed in a lot of smoke. I was close to passing out, lying on the ground, looking at the mangled bodies of my mother and father looking back at me. Their faces were filled with horror, but not a single drop of blood could be seen. I assume they'd been poisoned. As my consciousness drifted in and out, I began to think back of my brother, what he'd said and how he'd simply walked away, leaving his little sister to perish in the flames. I became thankful that my sisters had left the house that moment, they'd probably be returning to see the house alight. But one thing I could not forgive was the sin my brother had committed. I felt anger, hatred, and the desire for revenge. Even as a twelve year old girl, who had nearly everything she could possibly desire, I still felt the need for cold, hard vengeance. It was during that time I heard a voice call out to me.

_**"Do you wish to make a contract?"**_

Those seven simple words changed my life that day. I went from being a girl about to die, to a girl who was seeking the path she'd laid out for herself, knowing that at the end of it, I would perish by the hands of the very demon I'd contracted. The contract is very simple in terms. Sebastian works hard to protect me and help me accomplish my goal, looking after my every need, and then once it's all done, he will devour me, body and soul. That's the way a demon's contract works. Sebastian has contracted over people before, male and female alike, but he'd always been a house worker or a servant of some kind. In this house, working for myself, he was treated more like an equal, a member of the household, and that had slowly changed him, bit by bit. My sisters had welcomed him warmly after I had returned after being mysteriously missing for a year when the house had burnt down, with Sebastian in tow. My second eldest sister, Taina, the only one without kids, had taken me in, as per Mother and Father's will. My eldest sister Serina has five kids of her own, and my third eldest sister Eleanora had three kids of her own. And obviously my brother was completely out of the question.

* * *

"Young mistress? Are you almost done? We've gathered and prepared the necessary ingredients for tonight's dinner" Sebastian called out, standing behind me. I came out of my trance of viewing the past, turning to glance at him. He really was stunningly beautiful, but I guess that comes with the territory of being a demon. He raised his head, glancing at me with his gorgeous blood red eyes. His lips turned into a small smirk.

"You were remembering the past, weren't you young mistress?" he asked in a taunting way. I huffed to myself, turning away from him.

"So what? I'm not allowed to replay the event that drives me for revenge? And last I checked, my past and what I think in my spare time, are no concern of yours" I replied, trying to sound snarky. Sebastian merely chuckled to himself, bowing a little again.

"Of course, you are correct. What's done is done and there will be no correcting. You can only merely plot your revenge, then be devoured by myself at the very end" Sebastian stated, as if reminding me that I'd never escape from him.

"I am well aware of the rules of our contract. Trust me, I won't be forgetting any time soon. And besides, I know I'd never be able to escape from you, there's no use even trying" I reminded him, turning back to glare at him. Sebastian chuckled again, looking very pleased.

"I'm pleased you think that way, now I know I'll never have to worry" he stated, sounding so smug and chipper.

"Sebastian? Is Isabella ready? Can we begin cooking?" Taina asked, walking inside the kitchen with Serina and Eleanora in tow. All three of them were holding vegetables in their arms, almost to the point they couldn't carry them all.

"What on earth are you four going to cook?" I asked, raising a brow in curiosity.

"Yes, she's almost done. By the time the oven's ready, we'll have finished preparing. Just place the vegetables down on the table there and I will begin watching over the cooking" Sebastian instructed them, pointing at the table we used to prepare meals. All three of my sisters nodded, rushing over to follow instructions. I sighed.

"Fine… ignore me then…" I muttered, finally catching Sebastian's attention. He blinked at me in slight confusion, his eyes wider than normal, making the red in his eyes stand out more against his pure black hair and pale white skin.

"Hm? Oh, I'm terribly sorry young mistress. You see, I'm afraid when I'm conversing with your sisters I have to use all my attention and tolerance to deal with them. What did you ask?" he stated, making me begin giggling. He looked even more confused.

"Sorry, I know I shouldn't laugh, but after all this time I thought there was nothing you couldn't do, and here, right now, I hear you say you have a hard time dealing with my sisters! It was just hilarious!" I stated through my laughter. I wiped at my eyes, attempting to wipe the tears brimming in the corners of them.

"I asked you what the four of you were going to cook" I finally stated, seeing Sebastian smile, bowing his head a little.

"We are making a particular type of stew tonight. It's a cross between a curry and a stew. Don't worry; I know that foul look you're giving me. I know your tastes by now, I can assure you, you will like this. I know you cannot stand much spices or flavours; you have little taste buds which make you dislike more flavours than most people. Hence why you're such a picky eater. You're lucky you have me to cook for you; I was able to quickly figure out the cause of your horrible picky eating habits and put an end to them. I'm not able to stop the problem entirely, but I am able to accommodate for them, allowing you to eat foods you normally wouldn't dare touch" Sebastian announced, turning it into a rather lengthy speech, or lecture, I'm really not quite sure.

"You are so full of it… Just because my sisters worship you for being able to get me to eat more foods than they ever could…" I muttered, seeing him smirk at me. That was the only reason my sister Taina hadn't called up the cops and gotten Sebastian arrested for kidnapping, and was also one of the only reasons, at least I like to believe, that she let Sebastian stay. Ever since then, Sebastian has been my big brother, my father, my tutor and most importantly, my only true friend. I know what he'd say though if he heard those words come out of my mouth. He'd begin lecturing me on trusting a demon and how I shouldn't be so naïve.

"Hm? Young mistress? Is there something wrong?" Sebastian asked, seeing the small smile forming on my face. I really did confuse Sebastian a lot, I didn't think like most other humans he'd encountered, and my family was really crazy too, almost pushing Sebastian to his limit.

"Oh, nothing. Nothing at all" I replied, chuckling. Now it was my turn to be smug. Sebastian raised a brow in disapproval, sighing to himself before going to make sure my sisters didn't blow up the kitchen again. Honestly, the three of them were hopeless.

* * *

After I'd finished cleaning the oven, I stepped outside for some fresh air. After a few minutes of staring out into the night sky, I heard the door slide open as someone walked out behind me.

"Enjoying the full moon young mistress?" Sebastian asked, standing directly behind me. I smiled gently, turning to glance at him, the warm smile still on my face. Sebastian gasped a little in shock, blinking to make sure he hadn't been seeing things.

"Young mistress? What are you-?" Sebastian asked but was cut off abruptly when I turned to face him entirely, still smiling at him. My smile must've really thrown him off.

"Have you looked in the mirror or seen yourself during the moonlight? Believe it or not, the moonlight really makes your hair and eyes stand out, a lot. It's really quite pretty. I'll have to draw it for you someday" I stated, seeing him look taken aback, but then he smiled, trying to calm himself.

"I look forward to seeing this picture one day, young mistress" Sebastian stated, bowing his head a little, moving closer, inch by inch, until his forehead was a mere centimetre from mine. I was used to this already.

"Though you know, you should probably not let your guard down around me. I am a demon after all; I may decide to take advantage of you. After all, despite the fact of my being a demon, I am a full grown man, and you are a full grown woman. A man cannot guarantee that he can keep his urges in check, even if they happen to be a demon" Sebastian warned, making my eyes widen. I hadn't been expecting such a thing to ever come from his mouth. This certainly was surprising. Before I could voice my surprise, Sebastian had grabbed my wrist, twirling me in a dance before laying me back in one of his arms. The only thing stopping me from falling onto the ground was his one arm he had around my waist, supporting me. I was forced to look at him as he leaned over me, his eyes beginning to glow darkly, his smirk growing. He inched closer, till his face was right near my neck.

"Remember, no matter what, you belong to me, young mistress" Sebastian whispered in a soft, husky voice. I managed to control the small shiver rising in my spine, and looked at him.

"Sebastian?" I asked, seeing him look at me directly, his face mere inches from mine.

"Yes young mistress?" he asked, his curiosity piqued. I gave him an unamused expression, a slight glare on my face.

"Stop calling me young mistress, I have a name" I stated, earning a shocked and surprised look from him.


	2. Sickly

Chapter 1

Sickly

* * *

Blinding light rudely woke me that morning as Sebastian pulled the blinds, letting in the morning sun. I grumbled, turning to try and block out the sun.

"Come now young mistress, you wouldn't want to be late for school, now would you?" Sebastian asked, walking to the side of the bed I'd turned myself to, bending to peer directly into my face. I grumbled more, pulling the blanket up above my head, hiding from him.

"Screw school…" I muttered, sounding almost like a child having a tantrum. Despite being nineteen years old, I'm still in my final year of High School. That's because of the year I was missing with Sebastian. I'd had to catch up and repeat a year of school. Because of that, I wasn't too impressed with school anymore. It was boring, and honestly, I could learn so much more, much quicker, if Sebastian was teaching me. There was honestly no point in going. I heard Sebastian sigh, placing his hands on mine and pulling my hands down so the blanket would be removed from my face.

"Now young mistress, you don't want to sullen your family name, do you? Your family is prided for completing school with honours and completing university of the highest degrees. In order to do that, you need to go to school today" Sebastian tried to reason. I simply glared at him, and then turned my head to look out the window.

"To be honest… I feel like crap today… But I'll go, seen as you insist so strongly. But in condition, you stop calling me young mistress. Your butler habits are getting the better of you again" I replied, sighing and pulling myself up into a sitting position. Sebastian looked a little worried now, looking very concerned. I raised a brow.

"What? What is it Sebastian?" I asked, seeing his perfect brows furrow together, causing delicate wrinkles to begin forming between them.

"If you feel like you ever can't handle it, simply call my name, I'll be there in a heartbeat, okay?" Sebastian informed, making me sigh and nod at him. Honestly, he worries so much, but I guess that's the father role I'd assigned to him. I stood from my bed, managing to stop wincing from the sudden headache that coursed through my forehead.

"Alright, out, out!" I barked, getting behind Sebastian and pushing him out the room. He looked startled, and also confused.

"Isabella?" he asked, wondering why my face was so red. I looked down, continuing to push him out.

"I can't get dressed with you in the room! Out!" I barked again, pushing him out the room, getting ready to close the door. He turned to glance at me, still confused.

"I don't get what's so embarrassing. I've seen you naked thousands of times…" he pondered, making my cheeks burn furiously.

"Like I said, your butler habits are dying hard! And that was back when I was a child! I'm an adult now, so I can't just let you see me like that so casually!" I shouted, slamming the door. Geez, what was with him!? Saying stuff like that so casually. I mean sure, he used to be a butler and saw his previous master naked a lot. But I'm a female of the year 2013! As I stood there, fuming in my embarrassment I heard Sebastian chuckle, beginning to walk away from the door. I sighed, beginning to dress in my school uniform. Just when did women's clothing get so indecent? My uniform consisted of a shirt with the school brand on it, a checker jacket and a short, black skirt. The skirt didn't even make it half way between my knees and my hips.

"Looks like I'll be wearing mini shorts again" I muttered, grabbing my small black mini shorts and putting them on too. Finally I was ready, and I exited to see Sebastian outside my door again, holding my backpack.

"Well, shall we go?" he asked, also holding out a plate of toast. I gave him a weird look, snatching my bag and putting it on my shoulders.

"I can walk myself to school now Sebastian. You stay here and make sure my sisters don't wreck the house" I stated, grabbing the toast and shoving one of the corners into my mouth. The moment I took a bite, I didn't feel very hungry. Sebastian looked concerned again, his brows furrowed to make wrinkles. I sighed, raising my brows a bit. I pointed at him and then poked between his brows.

"Keep making that face and you'll be getting wrinkles in no time at all, demon or not" I stated, giggling. He glared at me, looking unimpressed. I couldn't help but grin, giggling.

"Are you sure you should be walking to school on your own when you claimed to not be feeling well?" Sebastian asked, adjusting the collar of his shirt, probably out of habit when he was a butler. I sighed, giving him an exasperated look.

"I'm nineteen; I don't need constant babysitting anymore. I can walk myself to school, thank you" I stated, walking to the door.

"Very well then… I shall be there to pick you up at the end of the day. Have a good day Isabella" Sebastian stated, bowing a little as he watched me walk out the door, closing the door behind myself. I sighed in relief. He was finally out of my hair. Sebastian could get a little suffocating every now and then; even I needed a little time to myself. I shook the thoughts out of my head, instantly regretting it, wincing in pain from my headache. Come on, time to get to school.

* * *

Getting to school had been easy, even in this heat, but what I was greeted with was anything other than pleasant.

"Where's your boyfriend Isabella? Did he finally see how ugly you are?" taunted one of the girls in my school. She's the typical school bully, followed by four other girls in her class, all just stuck up as each other. I sighed. Honestly, I didn't have the stamina or will to deal with her today.

"He's not my boyfriend and you know it. He's my older brother, clearly the fact that you fail to even remember that must show how stupid you truly can be. And because he hasn't shown much of any interest in you or your friends must prove how ugly you all must be" I retorted back, seeing the shocked and horrified looks on their faces. I don't see why they even bothered saying such things to me; it always got thrown back in their faces.

"You'll pay for that, I swear it Isabella! I'm going to wipe that smug grin right off your face!" she snapped back, her face going red from how angry she was. The same retort, always the same, nothing ever changes.

People in this school have been led to believe that Sebastian is my older brother. No one in my primary school had met my real brother, and during high school and the end of primary school when Sebastian had been walking me to school and back home we'd spread the rumour that he was my older brother. Only one person knew the truth, and that was Annie. She's the school reporter, writing articles for the school paper. She and I had been close friends back when I was little, so she'd been round to my house and met my real brother. Whether or not she remembered is a different story.

"Isabella! Isabella! Ready for PE today? It's first up!" shouted the person probably closest to being my friend. Hannah Porteous, she's bright, bubbly, clumsy and clingy. She stuck to me like glue at the beginning of High School, no matter how much I tried to shake her off, she stayed attached. I didn't want to be stuck to anyone; it'd make me want to stay after I'd fulfilled my goal. I sighed in annoyance.

"Yeah, I'm ready. But what're you so excited about it for? You suck at volleyball" I asked, seeing her flinch from my reminder.

"Yeah, but if you're playing it'll be fine! I'm good at serving, so you can protect me during the rest of the match! You're almost as strong as an entire team!" Hannah stated, giggling happily. Honestly, she wonders why I try and ditch her all the time. She relies on me way too heavily, I won't be here forever.

A sudden wave of dizziness made me stagger a little, but I managed to regain my senses and remain upright. Luckily Hannah had been walking away from me and hadn't seen my moment of weakness.

"Come on Isabella! Let's go!" Hannah shouted, turning to make sure I was still behind her. I sighed in irritation.

* * *

"Yes, I see. What is she up to now?" Sebastian asked, holding the home phone to his ear.

"Hehehe, she's currently getting ready to play some volleyball with her classmates. I dear say Sebastian; you seem to be rather possessive of this master of yours. You were never this attached to lord Ciel or anyone else. Could it be that… that demon heart of yours fancies her more than just for her soul?" replied the Under Taker who was sitting up in a tree, mobile phone in hand. Sebastian sighed, holding the bridge of his nose in his hand.

"Hardly… it's just this era has so many unseen dangers. One can never be too careful when it comes to the condition and safety of the soul they shall devour" Sebastian replied, sighing to himself. The Under Taker merely laughed.

"That lying to yourself will one day come and bite you in the ass my dear Sebastian" The Under Taker replied, chuckling more.

"Whatever… Just make sure you do your job" Sebastian retorted, his eye brow twitching.

"I'm afraid you're going to have to find someone else to watch your little mockingbird, I have to work now. Ta ta, Sebastian" The Under Taker stated, hanging up his mobile as he swung off the tree and began heading back to his shop. Sebastian looked at the phone, almost stunned. He sighed, thinking of other people he could ask to watch her. There was only one other person he knew that was still alive that could do it, but what would he have to pay in return? He shuddered at the thought.

* * *

Volleyball was one of the last things I wanted to play at the moment. My head was pounding and I couldn't think straight. When Hannah served the ball, it took all my strength and stamina just to keep the ball from hitting the ground on our side, as well as shout out what the other players needed to do. For some reason, without my instruction, all my other team members were ridiculously horrible at sports. I even let myself smack into the ground harshly to dig the ball back up into the air. Sebastian would be asking where these graze marks came from, geez.

I pulled myself back up onto my feet, shouting out the next command as the ball came flying at us. We returned it without much effort and it came flying back at us, straight at Hannah.

"Leave it!" I shouted, making us all jump away from the ball. The ball bounced outside the court and we won the match. My team members looked at me in amazement.

"Wow that was cool. How'd you know it would miss the court by a few centimetres?" Hannah asked, approaching me. I sighed, feeling dizzy.

"I could tell from the angle and force she hit the ball at" I replied, feeling incredibly dizzy. My vision was blurring and I was drenched in sweat. Maybe I was coming down with someone more than just the common cold.

"Hey, are you okay?" Hannah asked, approaching me. I was panting heavily, and suddenly I felt the landscape begin to sway. Black tainted my vision and soon it had been painted entirely in black. The same shade of black as Sebastian's hair.

* * *

When my eyes opened, I was greeted by Sebastian's face obnoxiously close to mine. I gasped, jumping up in shock, knocking our foreheads together. He flinched, covering the red mark on his forehead with his hand. I winced, covering my head with my own hand, my headache getting worse.

"Young mistress, are you alright?" Sebastian asked, tilting his head to look at me.

"I'm alright, in a sense. What happened? How did I get here?" I asked, looking around to see I was in the nurse's office.

"It appears you passed out during the game of volleyball" Sebastian explained, sitting on the edge of the bed.

"I'll say! You must've passed out as I was on my way there to watch you, cause when I arrived at the school, you were nowhere to be found!" stated an over dramatic voice I'd never heard before. I looked in the direction of the voice in shock and confusion to see a man standing there. He had really, really long red hair, yellow eyes and red glasses. He also wore a long red trench coat as well.

"U-Um… who?" I asked, pointing at him. He looked shocked suddenly, rushing to Sebastian and began clinging to his arm.

"How cruel Sebby! You never told her about me? About us?" he asked, sounding really hurt. Wait what!? My head hurt too much to try and process this.

"What us? There is no us. There is only you, there will never be an us!" Sebastian retorted, attempting to pry the red head off his arm.

"Who is this Sebastian?" I asked, tilting my head slightly.

"This is Grell, he's a Grim Reaper. For some reason he has this huge obsession with handsome men… Seems to think he'd a woman…" Sebastian explained, sounding annoyed about the red head.

"Come now Sebby! You make me sound so uncouth!" Grell exclaimed, sounding appalled. Sebastian turned to glare at him.

"Can we leave? My head hurts way too much…" I asked, holding my forehead in my hand. Sebastian stood, pushing Grell away, and then bowed to me.

"Certainly Isabella. We shall begin the trip home immediately" he stated, putting his arms behind my back and underneath my knees, and then lifted me up into his arms. I was too tired to fight back, letting my head rest by his chest.

"Now, let us return home" Sebastian stated, walking out the nurse's office as my world slipped back into black.


End file.
